The operation of a vessel involves not only the transportation of cargo or passengers, but also the continuous generation of waste. From food waste to plastics, oils and chemicals, onboard waste management is a critical issue for sustainability and environmental compliance. In this article, you will understand what happens to the waste produced on ships, how it is treated and which regulatory requirements guide this process.
Relevance
Maritime transportation is responsible for more than 80% of global trade, which naturally generates a significant volume of waste. Improper disposal can cause severe impacts on marine ecosystems, affecting biodiversity and compromising water quality.
For this reason, strict international regulations, such as the MARPOL Convention, established by the International Maritime Organization, regulate the treatment and disposal of waste in the maritime environment.
Types of Waste Generated on Board
Ships produce different categories of waste, each with specific treatment rules:
• Organic waste: food scraps
• Plastics: packaging, bottles and utensils
• Domestic waste: paper, glass and metal
• Oils and oily waste: originating from the engine room
• Hazardous waste: paints, solvents and chemicals
• Sewage: sanitary wastewater
Each type requires a specific process for storage, treatment and disposal.
How Is Waste Treated Inside the Ship?
Before any disposal, waste goes through controlled processes on board:
• Separation by type of waste
Waste is segregated according to its category, following international environmental protocols.
• Compaction and storage
Solid waste is compacted to reduce volume and stored in appropriate areas.
• Treatment of organic waste
It may be shredded and, in some cases, discharged at sea according to the rules.
• Treatment of oily water
Separation systems ensure that only water within the permitted limits is discharged.
• Sewage treatment
Modern ships have systems that treat wastewater before discharge.
Can Waste Be Thrown Into the Sea?
It depends on the type of waste and the operational conditions.
According to the MARPOL Convention:
• Plastics: disposal is completely prohibited
• Organic waste: permitted only under specific conditions, such as distance from the coast and proper treatment
• Oils: only after rigorous treatment and within legal limits
• Sewage: permitted if treated or in authorized areas
Failure to comply with these rules can result in high fines and international penalties.
What Happens to the Waste When the Ship Arrives at the Port?
A large portion of the waste is discharged on land, in specialized port facilities.
This waste is sent to:
• Waste management companies
• Recycling centers
• Hazardous waste treatment units
• Controlled landfills
This process ensures that disposal is carried out in an environmentally safe manner and in compliance with legislation.
Benefits of Proper Waste Management
Efficient onboard waste management brings several benefits:
• Reduction of marine pollution
• Preservation of ocean fauna and flora
• Compliance with international regulations
• Strengthening of corporate image
• More sustainable operations
Regulations
The main global reference is the MARPOL Convention, especially Annex V, which deals with garbage generated by ships.
This regulation is supervised by the International Maritime Organization and defines clear rules regarding:
• Types of waste
• Disposal methods
• Minimum distances from the coast
• Mandatory records, such as the Garbage Record Book
Vision for the Future
The maritime sector is evolving toward more sustainable practices, with a focus on reducing waste generation and increasing efficiency:
• Reduction of plastic use on board
• Advanced treatment technologies
• Onboard recycling programs
• Integration with ESG practices
• Development of more sustainable vessels
The waste produced on ships follows a strict process of separation, treatment and disposal, whether at sea under controlled conditions or on land, at ports. More than a legal requirement, proper waste management represents an essential commitment to ocean preservation and the sustainability of the maritime sector.
